Portable self-erecting silo

ABSTRACT

A portable hermetic silo is comprised of flexible, hermetic material. The silo is designed such that air may be introduced into a wall portion thereof, thus inflating the walls during filling of the silo. This allows the silo to be self-supporting while filling, and once the grain or other commodity is inside, air may be removed from the wall portion.

BACKGROUND

The present invention is directed to a portable silo for storing grains, in bulk, which is easily transportable and which is self-erecting.

Conventional silos configured to store grain or other commodities in bulk amounts of 10-50 tonnes are generally comprised of rigid materials such as metal, and are thus heavy and relatively expensive. Moreover, transporting such silos is difficult. It has previously been proposed to use a silo of flexible material, which could provide a lightweight alternative. However, introduction of grains or other commodities into such flexible materials is difficult, in that the sides of the silo need to be lifted during pouring of the commodity therein. Moreover, use of flexible material such as plastic may not be sufficiently hermetic to store the commodity for extended periods of time.

There is thus a need for a lightweight, portable, hermetic silo which is capable of storing bulk commodity for an extended period of time.

SUMMARY

There is provided, in accordance with embodiments of the present invention, a portable silo for hermetic storage, the silo including a bottom portion and a wall portion surrounding and sloping vertically upwards from the bottom portion, thus defining an enclosure for storage of a commodity, wherein the wall portion is comprised of a series of vertically sloping inflatable bladders (or ribs) around a circumference of the wall portion, creating a double walled structure.

In accordance with features in embodiments of the invention, the wall portion may be comprised of a material having a permeability to oxygen of less than 500 cc/m²/day and a permeability to water vapor of less than 9 g/m²/day. The silo may further include a sealable cover portion for placing on top of the wall portion and hermetically sealing the stored commodity in the portable silo.

In accordance with features in embodiments of the invention, the wall portion has an inward slope such that a bottom diameter of the wall portion is larger than a top diameter of the wall portion. Thus, the overall shape of the silo is substantially a truncated cone. In accordance with features in embodiments of the invention, the silo may further include one or more sealable outlet ports in the wall portion for removal of the stored commodity. The outlet port may be positioned in the wall portion near the bottom portion. Each of the inflatable bladder sections may include an inflation/deflation port for pumping air into the inflatable bladders and for removing air from the inflatable bladders. The portable silo may be capable of storing at least 10 tonnes to 100 tonnes of commodity therein, and the silo may have a weight of less than 300 kilograms, in the case of a 100 tonnes capacity, and less than 50 kilograms in the case of a 10 tonnes capacity.

There is provided, in accordance with additional embodiments of the present invention, a storage silo including a bottom portion for receiving a commodity thereon, said bottom portion configured for placement onto a surface, and a flexible wall portion surrounding the bottom portion and wherein in an extended configuration, the flexible wall portion is configured to extend upwards from the bottom portion thus forming an enclosure for storage of a commodity, the wall portion having an internal wall portion side and an external wall portion side separated from the internal wall portion side by a distance of at least 20 cm, and may be in a range of 20-50 centimeters or more. In one embodiment, the distance is approximately 35 centimeters, wherein the bottom portion the wall portion form substantially a truncated conical shape when the wall portion is in said extended configuration.

In accordance with features in embodiments of the invention, the extended configuration is obtained by providing air into a space between the internal wall portion side and the external wall portion side. In embodiments of the invention, the space is compartmentalized into a series of vertically extending inflatable bladders. The flexible wall portion may be comprised of a material having a permeability to oxygen of less than 500 c/m²/day and a permeability to water vapor of less than 9 g/m²/day.

The silo may further include a sealable cover portion for placing on top of the wall portion and hermetically sealing the stored commodity in the portable silo. In accordance with features in embodiments of the invention, the silo may further include one or more outlet ports in the wall portion for removal of the stored commodity. The outlet port may be positioned in the wall portion near the bottom portion. Removal of stored commodities can be done with a auger or with a suction pump. Each of the inflatable bladders may include an inflation/deflation port for pumping air into the inflatable bladders and optionally for removing air from the inflatable bladders. The portable silo may be capable of storing at least 10 tonnes of commodity therein, and the silo may have a weight of less than 300 kilograms, in the case of a 100 tonnes capacity, and less than 50 kilograms in the case of a 10 tonnes capacity.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and further advantages of the present invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective illustration of a portable silo 10 in accordance with embodiments of the present invention;

FIG. 2 is an illustration of a wall portion of the silo of FIG. 1, shown in greater detail;

FIG. 3 is an illustration of the silo of FIG. 1 with a cover portion;

FIG. 4 is a flow chart diagram illustration of a method of storing a commodity in the portable silo of FIG. 1 in embodiments of the present invention; and

FIGS. 5A-5E are illustrations of the steps of the method of FIG. 4.

It will be appreciated that for simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn accurately or to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity or several physical components may be included in one functional block or element. Further, where considered appropriate, reference numerals may be repeated among the drawings to indicate corresponding or analogous elements. Moreover, some of the blocks depicted in the drawings may be combined into a single function.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be understood by those of ordinary skill in the art that embodiments of the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components and structures may not have been described in detail so as not to obscure the present invention.

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

Reference is now made to FIG. 1, which is a perspective illustration of a portable silo 10 in accordance with embodiments of the present invention. Silo 10 includes a bottom portion 12 and a wall portion 14 surrounding bottom portion 12 and extendable upwards therefrom to form an enclosure 16 for storage of a commodity therein. Bottom portion 12 is configured for placement of the commodity thereon, and is configured to be placed on a surface. The surface on which the silo is located may be the ground, in which case the ground must be prepared to prevent rodents or others pests from entering from underneath. Alternatively, the surface may be a platform with rodent guards, for example.

Reference is now made to FIG. 2, which is a schematic illustration of wall portion 14 in greater detail. Wall portion 14 has an internal wall portion side 22 facing enclosure 16 and an external wall portion side 24 facing outwardly, with a space 26 between internal wall portion side 22 and external wall portion side 24. The distance 28 between internal wall portion side 22 and external wall portion side 24 is such that air pumped into space 26 may inflate portable silo 10 and will cause wall portion 14 to extend upwards. Distance 28 may be at least 35 cm. Thus, wall portion 14 is flexible and inflatable, such that when in a collapsed state, portable silo 10 may be moved from place to place and in the case of a 10 tonne capacity, weighs no more than 50 kilograms, while in the case of a 100 tonne capacity weighs no more than 300 kilograms. When air is pumped into space 26, wall portion 14, and more specifically the bladders or ribs in wall portion 14, becomes inflated and assumes an extended configuration, wherein wall portion 14 is extended substantially vertically. In some embodiments, wall portion 14 is sloped inwardly when inflated, thus forming a truncated conical shape, wherein a bottom diameter 40 of wall portion 14 is greater than a top diameter 42 of wall portion 14. While filling up enclosure 16 with the commodity, air is automatically released through an air relief system from space 26, to accommodate the maximum capacity of the enclosure 16 wherein silo 10 will retain its shape due to the presence of the commodity therein.

Returning now to FIG. 1, in embodiments of the invention, wall portion 14 includes a series of individual inflatable bladders (or ribs) 30, extending vertically and positioned around a circumference of wall portion 14, wherein each of inflatable bladders 30 has a space 26 for introduction of air therein. Each of inflatable bladders 30 may include an inflation/deflation port 32 and an air relief system port 33 for introducing air into and removing air from bladders 30. In a preferred embodiment, a single inflation/deflation port 32 may be used to inflate and deflate all of bladders 30 together. In this embodiment, bladders 30 are connected to one another via an inflation tube. An outlet port 34 may be included on wall portion 14, wherein outlet port 34 is configured for removal of the commodity from enclosure 16. In some embodiments, outlet port 34 is located at a bottom of wall portion 14 close to bottom portion 12. The commodity may be removed by a horizontal sweep auger, as is known in the art or by gravitational force. In other embodiments, outlet port 34 may be positioned in any other location on wall portion 14 and contents may be removed using a sweep auger or a suction mechanism.

Reference is now made to FIG. 3, which is an illustration of silo 10 with a cover portion 36, which is designed to be placed on top of wall portion 14 when silo 10 is full. Cover portion 36 is hermetically sealed, for example, by a specially designed hermetic zipper, wherein one half of the zipper is on cover portion 36 and the other half of the zipper is on top of the wall portion so that the commodity held within enclosure 16 (as depicted in FIG. 2) remains safe from infestation. In order to maintain hermeticity, wall portion 14 and optionally bottom portion 12 are comprised of a lightweight, hermetic material, such as disclosed in U.S. Pat. No. 8,528,305, issued on Sep. 10, 2013, and incorporated by reference herein in its entirety, or of thicker material such as 1 mm PVC.

The material may include an outer layer and an inner layer, with a middle layer sandwiched between the outer and inner layers. The outer layer, inner layer and middle layer may be co-extruded. The purpose of the middle layer is to provide low permeability to oxygen, while the outer and inner layers are designed to add strength to the middle layer and to provide a low permeability to water vapor. The outer and inner layers may be comprised of polymeric material, such as polyethylene, while the middle layer is comprised of a very low permeability material to oxygen, such as, for example, nylon. An example of such a co-extruded material is PLASTOBARR N 80, manufactured and sold by Plastopil Ltd., Hazorea, Israel, originally designed for chemical and bacteriological warfare protection and now also used in retail vacuum packaging of meats, fish, or cheese (“vacuum pouches”) to preserve freshness, and also used in retail packaging for preserving freshness of fresh vegetables. This material includes a thin co-extruded flexible triple-layer material (PE/PA/PE), including an outer layer and an inner layer of one polymeric material (polyethylene), and a very low permeability middle layer sandwiched between the two outer layers. In some embodiments, any one or several of outer layer, inner layer and middle layer may include multiple layers of material or a combination of materials. For example, a material which has low permeability to oxygen, but not to moisture may be combined with a material which has low permeability to water but not to oxygen. It should be readily apparent that the middle layer may be comprised of any low permeability barrier material suitable for sandwiching between an outer layer and an inner layer.

Silo 10, when manufactured from these or similar materials will have a very low permeability to Oxygen, Carbon Dioxide, and water vapor, even when the total thickness is under 1 mm. Thus, the permeability per unit area for Oxygen is 500 cc/m²/day or less, and permeability for water vapor is 9 grams/m²/day or less. The term “ultra low permeability” for purposes of the present invention thus refers to permeability to Oxygen of less than 100 cc/m²/day and to water vapor less of than 15 g/m²/day.

Use of a silo with hermetic properties such as the ones disclosed herein provide the commodity with protection from insect infestation and mold growth solely based upon the ultra-low permeability packaging material and without the use of a pesticide and without the use of vacuum pumping after hermetically sealing the container. The available oxygen is consumed by infesting insects including eggs, larva, pupae, and adult insects to a level low enough to cause the death of the infesting insects, and is further configured to protect the commodity in the hermetically sealed storage container by inhibiting mold and fungus growth through the low level of oxygen and lack of a high humidity.

It should be readily apparent that the silo of the present invention allows for storage of bulk commodity without the need for bags to support the flexible exterior, while maintaining a hermetic environment. Moreover, the silo of the present invention may accommodate 10-100 tonnes or more of a commodity, a feature which is not possible using other portable silo configurations.

Reference is now made to FIG. 4, which is a flow chart diagram illustration of a method 200 of storing a commodity in a portable silo, in accordance with embodiments of the present invention. Reference is also made to FIGS. 5A-5E, which are graphical illustrations of the method of FIG. 4.

First, a portable silo 10 is provided (step 202) at a desired location. Silo 10 is comprised of a flexible material, and is lightweight, which enables silo 10 to be transported to the desired location. Silo 10 is shown in a collapsed state in FIG. 5A. Next, wall portion 14 is inflated (step 204) by pumping air into space 26 of wall portion 14. This may be done using a battery operated blower 50 as shown in FIG. 5B, and may be done using compressed air at low pressure, which is enough to enable wall portion 14 to inflate and to extend upwards. Next, a commodity such as grain is introduced (step 206) into silo 10 through the open top via, for example, an auger or with a suction pump 52. Silo 10 is shown in a partially inflated state in FIG. 5B. During the step of introducing a commodity (step 206), as the presence of the commodity therein is sufficient to hold wall portion 14 in its extended position, air is removed (step 208) from space 26 of wall portion 14 via an air relief system including an air relief port 33, as shown in FIG. 5E, in order to accommodate the maximum capacity of silo 10. This is typically done immediately after the step of introducing the commodity. The steps of introducing the commodity (step 206) and removing of air/deflating the wall (step 208) may be repeated until silo 10 is full. As shown in FIG. 5D, cover portion 36 is then placed on top of wall portion 14 and silo 10 is hermetically sealed (step 212). The commodity may be stored in this way for a period of one year or more. When it is desired to empty the silo of the commodity, either partially or fully, the commodity is removed (step 214) via a removal mechanism 54 such as an auger or suction pump, as shown in FIG. 5E.

Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. 

What is claimed is:
 1. A portable silo for hermetic storage of bulk, dry commodities, the silo comprised of flexible material, the silo comprising: a bottom portion; and a wall portion surrounding and sloping vertically upwards from said bottom portion, thus defining an enclosure for storage of a commodity, wherein the wall portion is comprised of a series of sloping, vertically extending inflatable bladders or ribs around a circumference of the wall portion, forming a double-walled structure.
 2. The portable silo of claim 1, wherein the wall portion is comprised of a material having a permeability to oxygen of less than 500 c/m²/day and a permeability to water vapor of less than 9 g/m²/day.
 3. The portable silo of claim 1, further comprising a sealable cover portion on top of the wall portion and hermetically sealing the stored commodity in the portable silo.
 4. The portable silo of claim 1, wherein the wall portion has an inward slope such that a bottom diameter of the wall portion is larger than a top diameter of the wall portion.
 5. The portable silo of claim 1, having substantially a truncated conical shape.
 6. The portable silo of claim 1, further comprising an outlet port in the wall portion for removal of the stored commodity.
 7. The portable silo of claim 6, wherein the outlet port is positioned in the wall portion near the bottom portion.
 8. The portable silo of claim 1, wherein each of the inflatable bladders individually or collectively includes an inflation/deflation and air relief system port for pumping air into the inflatable bladders and for removing air from the inflatable bladders.
 9. The portable silo of claim 1, wherein said portable silo is capable of storing at least 10 tonnes of commodity therein, and wherein said portable silo weighs less than 300 kg.
 10. A storage silo comprising: a bottom portion for receiving a commodity thereon; and a flexible wall portion surrounding said bottom portion and wherein in an extended configuration, said flexible wall portion is configured to extend upwards from said bottom portion thus forming an enclosure for storage of a commodity, the wall portion having an internal wall portion side and an external wall portion side separated from said internal wall portion side by a distance of at least 20 cm, wherein said bottom portion and said wall portion form substantially a truncated conical shape when said wall portion is in said extended configuration.
 11. The storage silo of claim 10, wherein said extended configuration is made rigid by providing air into a space between said internal wall portion side and said external wall portion side.
 12. The storage silo of claim 11, wherein said space is compartmentalized into a series of vertically extending inflatable bladders.
 13. The storage silo of claim 10, wherein the flexible wall portion is comprised of a material having a permeability to oxygen of less than 500 cc/m²/day and a permeability to water vapor of less than 9 g/m²/day.
 14. The storage silo of claim 10, further comprising a sealable cover portion for placing on top of the flexible wall portion and hermetically sealing the stored commodity in the storage silo.
 15. The storage silo of claim 10, further comprising an outlet port in the flexible wall portion for removal of the stored commodity.
 16. The storage silo of claim 15, wherein the outlet port is positioned in the flexible wall portion near the bottom portion.
 17. The storage silo of claim 12, wherein the inflatable bladders include an inflation/deflation and air relief system port for pumping air into the inflatable bladders and for removing air from the inflatable bladders.
 18. The storage silo of claim 1, wherein said storage silo is capable of storing at least 10 tonnes of commodity therein, and wherein said storage silo weighs less than 300 kg. 